Wireless information communication systems currently exist which connect mobile wireless devices, e.g., cell phones, personal data assistants (PDAs), laptop computers, Internet appliances or other suitable devices, also known as mobile wireless communications devices, through a network of base stations, e.g., wireless wide area network (WWAN) base stations and WLAN transmitters, also known as wireless communications networks. For example, such systems are known to utilize both (or either) WWANs and WLANs. WWAN systems are known to include, for example, the following systems: General Packet Radio Service (GPRS), Code-Division Multiple Access (CDMA), Wideband CDMA (W-CDMA) and Universal Mobile Telecommunications System (UMTS). WLAN systems, on the other hand, typically include short range wireless local-area networks (WLANs) such as Bluetooth or IEEE 802.11 systems.
Wireless information communication systems are known to handle information, including, voice, video, pictures, text, and other types of data. Such systems are also known to handle very large files of information, particularly those characterized by their continuous streams of video or audio, also known as streaming information. A typical example of streaming information is a file containing video, such as a movie clip that is linked to a web page or live audio or video. Streaming information is typically handled in such a way as to allow for a recipient to begin displaying the information before the entire file is transmitted. For the intended effect, streaming information must be available in a steady stream so that it can be reproduced in a continuous manner. If the information does not arrive quickly enough the presentation will not be smooth. Since such information is said to be streamed to a receiving device, the sending of such information is often described as “streaming information.”
A known bottleneck currently exists in the transmission of streaming information to wireless mobile devices. This bottleneck occurs where such wireless mobile devices, while receiving streaming information, cross base station service area boundaries, also known as cellular area boundaries, where the mobile wireless device travels from one base station service area, or cell, into an adjacent base station service area, or cell, causing the mobile wireless device to be connected with a new base station. When a mobile wireless device is connected to a particular base station, i.e., is receiving streaming information therefrom, such base stations, or network infrastructure, are said to be supporting communication of the mobile wireless device. More specifically, wireless mobile devices, while in one cell site (e.g., connected to particular base station), scan other available cell sites (supported by base station controllers and mobile switching centers) to locate the best signal and shift among such cell sites. The switches are typically connected through an asynchronous transfer mode (ATM) link and when a new cell site is identified the ATM backbone pipes the streaming information to the identified switch. Here, delays are introduced because the new base station is initially unaware of the mobile wireless device's association with the streaming information. Once the new base station is aware of a need of the particular streaming information, it must then make a network request to acquire the information. It is not until the requested information reaches the new base station that the information can be passed on to the mobile wireless device. As a result, the process of a wireless mobile wireless device being handed off to a new base station results in a delay in the sending of streaming information to such devices.
At least one design attempts to reduce the latencies involved with a mobile wireless device crossing between wireless base stations coverage areas by detecting such a crossing prior to its occurrence, and copying the information intended for transmission from the current base station to the next base station. In the case of handling streaming information, this design would also, as part of the copying of information to the next base station, copy the current packet information such that the new base station could continue to transfer the streaming information in a continuous fashion. In such systems a mobile wireless device monitors the electrical signal intensity of wireless cells and predicts that it is moving toward a particular wireless cell. The mobile wireless device then notifies a management device that the mobile wireless device will soon be traveling into a particular new base station service area, or cellular area, and to copy the entire current base station related cache information into the predicted new base station related cache. Cache is a high speed storage mechanism. Cache is effective because most programs access the same data or instructions over and over. Here, cache is being used to solve a problem of accessing time-dependent streaming information. This use of cache helps network load balancing and optimum routing. Further, if streaming information is stored in such a cache, and if a portion of such streaming information had since been transmitted to the mobile wireless device, then, the copying of the entire cache to the new base station would include copying of a sending overlapping portion (that already sent to the mobile wireless device) of such current streaming information into the new base station's related cache. In addition to the mobile wireless device identifying a next base station, this design also allows for a management device connected to the network to make the next base station identification by logging the base station service areas to which the mobile wireless device has been attached, and then identifying the immediate next base station or base station service area based on the knowledge of the location of the previous base stations or base station service areas. In either case the entire cache of a previous base station is copied to the next base station.
It should be noted that the above described design was not directed to WLANs. It is known that WLANs generally operate in a fashion significantly different than WWANs. For example, WLANs utilize small buffers, rather than cache, to store information associated with their base stations. Such buffers differ from cache in that they are a few kilobytes to a few megabytes, where cache is generally of the order of gigabytes. In addition, WLANs are not known to utilize predictive base station functionality, WLANs usually detect the entry of a wireless mobile wireless device into a another base station service area and transfer control to the new base station. In determining the next base station, or access point, WLANs typically use signal strength and signal to noise ratios. The current WLAN base station, or access point, is then able to initiate a handoff to this next base station. The wireless mobile device then scans for base stations, or access points, using what is typically known as a MAC layer function. The wireless mobile device listens to an base station, or access point, during the scan and creates a prioritized list of access points to choose from.
There are also systems that predict the future location of an in-transit mobile computer based upon the mobile computer's current location, velocity and direction. Such systems use this information for the purpose of retrieving geography based information associated with the predicted location. More specifically, the geography based information is used to retrieve local street maps or to retrieve other information based upon the physical surroundings of where the wireless mobile computer is expected to be at a future particular time. The location of the mobile computer is determined or acquired by using GPS receivers, cellular network triangulation positioning systems, and the cell IDs of the associated cellular wireless phone systems. Further, moving condition controllers and moving condition memory are used in predicting the future position of the mobile computers. Such systems do not address the sending of segments of streaming information to predicted network base stations.
In recent years the use of streaming information has continued to grow. With this growth, and the corresponding increase in the quantity and size of the requests for this information, there continues to be ever heavier burdens placed upon information communication systems As a result, there continues to be strong market forces in favor of the development of new ways to quickly deliver and process streaming information.